MTP5.09 Loss of bone morphogenetic proteins (BMP) and BMP receptors in gastric cancers is associated with disease progression and poor prognosis

Aims The present study aimed to examine the expression of some BMPs and their receptors (BMPR) at the transcript level in a clinical cohort of gastric cancer (GC) to evaluate their expression and the correlation between their expression and prognosis. Methods The transcript expression of BMPs and two receptors was examined in a clinical cohort of gastric cancer tissue samples comprising 324 primary tumour tissues and paired adjacent normal gastric tissues using real time PCR. Results A marked reduction was seen in the expression of BMP-3, BMP-4, BMP-6, BMP-7 and BMPR2 in the gastric tumours compared with their transcript levels in the adjacent normal tissues. In contrast to the reduced or loss of expression of those BMPs and receptor, higher transcript levels of BMP4 and BMP7 in the primary tumours were significantly associated with deaths of patients, p=0.006 and p=0.027, respectively. Higher expression levels of BMPR1B were also seen in those tumours presented distant metastases at diagnosis of the disease, median=4.1, p=0.0298 compared with the tumours without distant metastasis (median=0.5). An increased expression BMPR1B was also seen in tumours with N3 stage of lymph node metastasis, p=0.023 compared with its expression in the tumours without lymph node metastasis. Conclusion Transcript levels of BMP-3, BMP-4, BMP-6, BMP-7 and BMPR2 were reduced in gastric cancers. However, higher BMP4, BMP7 and BMPR1B expression levels were associated with the death or distant metastases from the disease. Further research is required for elucidate the exact roles played by these BMPs and BMPR1B in gastric cancer.